Pressure tracings

Question 1

Anacrotic notch

Answer 1

associated w turbulent flow during ejection
o May be apparent in systolic pressure rise
o Indicate abnormality in AoV or proximal Ao

Question 2

Normal Ao peak systolic P

Answer 2

90-140mmHg

Question 3

Dicrotic notch

Answer 3

associated w semilunar valve closure
o Present in systolic pressure decline

Question 4

Normal Ao diastolic P

Answer 4

60-90mmHg

Question 5

Normal ventricular pressures

Answer 5

• Systolic pressure correspond to associated artery
• Diastolic pressure similar to atrial pressure => close to 0
• End diastolic pressure: measured after atrial contraction (a wave), before systolic pressure rise

Question 6

2 components of central AoP

Answer 6

• Pressure wave from forward flow (LV ejection)
• Pressure wave from reflected waves

Question 7

Define reflected waves

Answer 7

o Generated by areas of resistance to blood flow: branch points, tortuous vessels
o Directed back to the heart
 When meet AoV, generate additional smaller forward impulses
 Particularly in peripheral arterial waveforms

Question 8

When are reflected waves significant

Answer 8

 CHF
 AI
 Systemic hypertension
 incr Ao stiffness (age)
 Ao or iliofemoral obstruction
 Tortuosity and arterial vasoconstriction

Question 9

When are reflected waves diminished

Answer 9

 Vasodilation
 Hypotension
 Hypovolemia

Question 10

Why peak systolic P higher vs central AoP

Answer 10

• Peak systolic pressure > central aortic pressure by 10-20mmHg due to peripheral amplification from reflected waves

Question 11

What changes in waveform occur in peripheral arterial tree

Answer 11

• Further in arterial tree: pressure waveform change
  o Steeper upstroke
  o Narrow systolic portion
  o Late, decr or absent dicrotic notch

Question 12

Normal RA waveform

Answer 12

• 3 positive waves
  o a wave: atrial contraction
   Follow P wave on ECG (after 80ms)
  o c wave: closed valve bulge into atrium during IVCT
   During downslope of a wave
  o v wave: late systole
   Atrial filling gradually incr pressure
   Closed AV valve
   Peak at end of systole => maximal filling
• End of T wave
• 2 downslopes: x and y descent
  o x descent: atrial relaxation => decr pressure + lower annulus
  o y descent: emptying of atrium after AV valve open

Question 13

LA vs RA waveform

Answer 13

LA: incr mean pressure, dominant v wave

RA : dominant a wave

Question 14

Normal RAP and variation

Answer 14

2-6mmHg

• With inspiration: mean RAP decr due to decr intrathoracic pressures
  o incr passive RV filling
  o More prominent y descent

Question 15

RAP changes PS

Answer 15

• Pressure gradient across the PV => incr RV systolic pressure
  o RVH => decr RV compliance => incr end diastolic RV pressure
  o incr RA pressure
• incr a wave => need to incr RA pressure to compensate incr RV pressure
  o TS, Rv failure, PH, PS

Question 16

RAP changes w TR

Answer 16

• Volume overload of RV and RA
  o Dilation of RV => incr TR
  o incr RA pressure
  o decr CO
• Changes in RA waveform
  o Attenuated x descent
  o c-v wave: systolic wave with peak dome contour
  o v wave prominent
  o Rapid y descent => incr volume
  o incrmid to late systolic v wave

Question 17

RAP changes AVB

Answer 17

• c wave: follow a wave during
  P-R interval
• 1st degree AVB => incr c wave
• Cannon a wave: atrial contraction against closed valves

Question 18

RAP changes constrictive pericarditis

Answer 18

M or W pattern
o v wave > a wave => non-compliant RA
o Rapid y descent
 Rapid atrial emptying in early diastole
 incr RA pressure
 Underfilled RV
o Absence of respiratory variation

Question 19

Pathophys of constrictive pericarditis

Answer 19

o Rigid shell encasing the heart
 Limit total volume of blood that enter cardiac chambers => decr ventricular diastolic filling
 Early diastole: rapid filling
* > rapid vs normal because of underfilled state of RV
 Mid diastole: abrupt stop => rapid incr pressure
o Ventricular interdependence
 Volume/pressure of one chamber affect/is reflected in the other
o Dissociation of intrapleural/intracardiac pressures
 Inspiration: decr intrathoracic pressures but not intracardiac
* incr venous return into thorax but not heart
* decr pulmonary venous pressures
o decr LV filling + decr LV pressure/preload => decr SV
o incr RV filling + incr RV pressure
 Expiration = opposite
* incr intrapleural and pulmonary venous pressure
* incr PVs pressure => incr LV filling
 Discordance of RV and LV systolic pressures in inspiration: spe/sens for constrictive pericarditis
* vs RCM => equal decline in LV and RV systolic pressures w inspiration

Question 20

RV changes constrictive pericarditis

Answer 20

o Dip and plateau pattern = SQUARE ROOT SIGN

Question 21

RAP changes cardiac tamponade

Answer 21

o Absence of y descent => rapid ventricular filling
o Equally elevated a and v waves
o Undulating flat line: elevated equalized right sided pressures
o Kussmaul’s sign:
 incr RA pressure during inspiration
 incr RA waveform w xY or xy pattern

Question 22

RAP changes Afib

Answer 22

• Absence of a wave
• x descent may be present because of annulus downward motion